An Adaptive Loop Canceller for Relay Stations in Digital Terrestrial Broadcasting Systems

A loop canceller is described for coping with loop coupling at relay stations for OFDM (orthogonal frequency division multiplexing) SFNs (single frequency networks) in terrestrial digital broadcasting systems. An iteratively adaptive algorithm based on the least means square method is used for the loop cancellation filter. Use of this adaptive filter reduces hardware complexity and minimizes hardware size. Computer simulation showed that the proposed canceller is effective for loop cancellation in actual OFDM digital broadcasting systems.